浸透した下流RNAヘアピンが動的にスタートコドン選択を決定する
Yezi Xiang1,2, Wenze Huang3,4,5, Lianmei Tan6
1Department of Biology, Duke University, Durham, NC, USA.
Nature
|September 6, 2023
まとめ
生物はトランスレーションによる再プログラムによって 変化する条件に適応します この研究では,上流のスタートコドン (uAUGs) の下流にある特定のRNA構造が翻訳開始を制御し,このメカニズムが王国全体で保存されていることが明らかになりました.
科学分野:
- 分子生物学
- 遺伝学
- 生物化学
背景:
- 翻訳的な再プログラミングは 環境の変化に適応することを可能にします
- メッセンジャーRNA (mRNA) の上流スタートコドン (uAUG) は,代替スタートサイトを提供することで翻訳を調節する.
- 異なる条件下で選択的な翻訳を開始するメカニズムは完全に理解されていません.
研究 の 目的:
- アラビドプシスのパターン誘発免疫における選択的翻訳開始の調節を調査する.
- アップストリーム・オープン・リーディング・フレーム (uORF) と関連するRNA構造のトランスレーション制御における役割を特定する.
- このメカニズムの保存とダイナミックな調節をヒト細胞で探求する.
主な方法:
- アラビドプシスのトランスレーションと構造分析を統合した.
- uAUGs (uAUG-ds) の下流のRNA構造を特定し予測するためのディープラーニングモデリング.
- 植物とヒトの細胞におけるRNAヘリコース機能の比較分析.
主要な成果:
- 免疫誘発翻訳のトランスクリプトは,uORFで強化されます.
- uAUG の下流にあるヘアピン構造 (uAUG-ds) は,感染していない状態で選択的な uAUG 翻訳を媒介する.
- 誘導RNAヘリケーゼは,免疫的挑戦時にuAUG-ds構造を解消し,防御タンパク質の翻訳を可能にします.
- uAUG-ds媒介による調節はヒト細胞に保存されます.
結論:
- mRNA構造は,トランスレーション開始コードンの選択を動的に制御する.
- uAUG-dsは,王国間のトランスレーション再プログラムの一般的なメカニズムとして機能します.
- RNAヘリケーズによるmRNA構造のダイナミックな改造は,適応翻訳に不可欠である.
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